Improved iron bridge



inaterexplained.

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'1,.1B.WHITE, 0'F NEW'BVRIGHTON, PENNSYLVANIA. -Letters No.'87,741, datedMa/rch 9, 1869; cntedated February 27, 1869.

'MRO'V'ED IRON BRIDGE.

The Schedule referred to in these Letters Patent and making nart of the same.

To all whom tt 'ma/y concern.-

Be it know that I, 'rn-B; WHITE', of New Brighton, in the county of Beaver, and State of Pennsylvania, have invented certain new and useful Improvements in the Gonstruction of Iron Bridges; and I do hereby -declare `that the following is a full, clear, and exact description thereof,.reference being had to the accompanying drawings, making part of this specification, and to the letters of reference marked thereon, like letters indicating like parts wherever they occur.

To enable others skilled'in the art to construct and use my invention, I will proceed to describe it.

My invention consists in a novel manner of constructing ironbeams for braces, andsimilar purposes,

in building bridges and similar structures, and also in forming a combined tie-bar and angle-iron, orrstep, for braces, of wrought-iron or steel, in one piece, as here- Figure l is a side elevation of a beam -constructed onmyplan;

'Figure `2 is an end view of the same;

Figure 3 is the same slightly modified;

Figure'4 is aface or planview of my combined tiebar and brace-step; and

Figure 5 is an end view'of the same.-

Figures 6, 7, and 8, represent portions of a bridge, with these improved parts in place, as they are intended to be used.A

In constructing bridges and similar structures of iron,

and in all Vcases where iron girders, beams, or braces are used, it is an object to combine the greatest'po'ssible amount of strength with theleast possible weight,

and'for this purposemany forms of both solid and tubular bars have been designed.` In braces, the element of rigidity is also important, and it is for this use mainly that my present form of beam is designed. w

To construct'my improved beam, I first form a series of bars, curved transversely, as .represented by Vc,

figs. 2 and 3, by rolling them in that shape. I thenl take four of' these bars, after having made holes for rivets along their edges, and place their convex sides inward, and unite them firmly by rivets, `as showniu figs. 1, 2, and 3.'y lBy this means I form a beam that is tubular andI light, and which is provided with four radial ilanges, which greatly stiften it, and tend to prevent exure, when used as abra'ce, and which,4 at the same time, form convenient and salient points for boltingr or otherwise attaching other bars or pieces to them.

When these beamsare to be used as chords, or girders, I construct them with a central dat bar, bolted or riveted vertically betweenthe bars a, as' represented by b inlig. 3. y.

In constructing iron, and even wooden bridges, it-is customary to use cast-iron angle-blocks, to receive and hold the ends ofthe braces and bolts.

Experience has shown that these blocks are exceedingly liable to crack or break, lespecially at the point where holes are made to receive the bolts that pass through them.

When these cast-iron blocks are used in building iron bridges, having two or more chords, or girders, side by side, it is customary to unite or tie the girders together, by means of separate wrought-iron bars, bolted transversely' across them. I

To form a safer, lighter, 'and stronger article, which shall answer the combined purpose of tie-bar and angle-block for the braces, I constructa wroughtiron plate, as represented by B, figs. 4 and 5, This bar may be made of any desired length, and with a horizontal flange, c, ou each side, to bolt it fast to the beams or girders, and its central portion raised in a V-form, as shown in fig. 5, the faces d ofthe raised portion standing at an angle, to correspond with the angle at which it is intended to place the braces, the latter being indicated by dotted linesin g. 5, and beingV shown in side elevation, with the plates Bin position, both` at top and bottom, inlfig. 7; iig. 8 being a front view of three braces,similarly arranged, the two outside ones being inclined in'one direction, and the central one, in the opposite direction.

Fig. 6 is a plan view of' a bridge-bed, or frame, consisting of a series of three girders, or chordson each side. and showing the improved tie-bar and brace-block, applied, by being bolted thereon, ready 'to receive the braces.

In case the structure is very heavy` or large, the bar B may be stii'ened, or supported transversely, where the braces are to rest upon it, by forming it with cross-bars n, as shown in iig. 5,' and, if desired,

a projecting piece, or lug o, may be formed thereon, andvmade to lit between the girders A, or to be bolted to the sides thereof.

It is obvious that this plate is equally well adapted to wooden truss-bridges as 'to iron.

I would here remark that these beams A and bars B are more especially intended for use in connection with the improved iron beam recently invented by me,

and on which I have already made application fora 

